Medial malleolus screws: out in one view and out

Operative vs Nonoperative Management of Unstable Medial Malleolus Fractures: A Randomized Clinical Trial

Importance

Unstable ankle fractures are routinely managed operatively. However, because of soft tissue and implant-related complications, recent literature has reported on the nonoperative management of well-reduced medial malleolus fractures after fibular stabilization, but with limited evidence supporting the routine application.

Objective

To assess the superiority of internal fixation of well-reduced (displacement ≤2 mm) medial malleolus fractures compared with nonfixation after fibular stabilization.

Design, Setting, and Participants

This superiority, pragmatic, parallel, prospective randomized clinical trial was conducted from October 1, 2017, to August 31, 2021. A total of 154 adult participants (≥16 years) with a closed, unstable bimalleolar or trimalleolar ankle fracture requiring surgery at an academic major trauma center in the UK were assessed. Exclusion criteria included injuries with no medial-sided fracture, open fractures, neurovascular injury, and the inability to comply with follow-up. Data analysis was performed in July 2022 and confirmed in September 2023.

Interventions

Once the lateral (and where appropriate, posterior) malleolus had been fixed and satisfactory intraoperative reduction of the medial malleolus fracture was confirmed by the operating surgeon, participants were randomly allocated to fixation (n = 78) or nonfixation (n = 76) of the medial malleolus.

Main Outcome and Measure

Olerud-Molander Ankle Score (OMAS) 1 year after randomization (range, 0-100 points, with 0 indicating worst possible outcome and 100 indicating best possible outcome).

Results

Among 154 randomized participants (mean [SD] age, 56.5 [16.7] years; 119 [77%] female), 144 (94%) completed the trial. At 1 year, the median OMAS was 80.0 (IQR, 60.0-90.0) in the fixation group compared with 72.5 (IQR, 55.0-90.0) in the nonfixation group (P = .17). Complication rates were comparable. Significantly more patients in the nonfixation group developed a radiographic nonunion (20% vs 0%; P < .001), with 8 of 13 clinically asymptomatic; 1 patient required surgical reintervention for this. Fracture type and reduction quality appeared to influence fracture union and patient outcome.

Conclusions and Relevance

In this randomized clinical trial comparing internal fixation of well-reduced medial malleolus fractures with nonfixation, after fibular stabilization, fixation was not superior according to the primary outcome. However, 1 in 5 patients developed a radiographic nonunion after nonfixation, and although the reintervention rate to manage this was low, the future implications are unknown. These results support selective nonfixation of anatomically reduced medial malleolar fractures after fibular stabilization.

Trial Registration

ClinicalTrials.gov Identifier: NCT03362229.

Periarticular screws: what's in and what's out of the joint?

Periarticular hardware placement can be challenging and a source of angst for orthopaedic surgeons due to fear of penetrating the articular surface and causing undue harm to the joint. In recent years, many surgeons have turned to computed tomography (CT) and other intraoperative or postoperative modalities to determine whether hardware is truly extraarticular in areas of complex anatomy. Yet, these adjuncts are expensive, time consuming, and often unnecessary given the advancement in understanding of intraoperative fluoroscopy. We present a review article with the goal of empowering surgeons to leave the operating room, with fluoroscopy alone, assured that all hardware is beneath the articular surface that is being worked on. By understanding a simple concept, surgeons can extrapolate the information in this article to any joint and bony surface in the body. While targeted at both residents and surgeons who may not have completed a trauma fellowship, this review can benefit all orthopaedic surgeons alike.

A novel method to assess intraarticular screw penetration into the joint space

Objectives

This study aims to propose a novel method to detect articular penetration of screws by relying on their electrical conductivity properties and control the validity of this method.

Materials and methods

In this ex vivo study, conducted between June 2017 and August 2017, we used five fresh sheep shoulder joints. First, the shoulder joint space was filled with saline solution. An insulated cannula was placed in the joint capsule, and a conductive wire was introduced into the joint via this cannula. A single titanium screw was inserted from the tuberculum majus into the posteroinferior quadrant of the humeral head under fluoroscopic observation. Conductivity was continuously measured using a digital multimeter. When a sudden decrease in conduction resistance was detected, fluoroscopic images were obtained in the anteroposterior (AP) and lateral directions. These images were assessed for penetration by a blinded surgeon. Penetration was confirmed by dissection of the joint.

Results

There was a significant decrease in electrical resistance when screw penetration occurred (p<0.001). All penetration events were confirmed using our novel method. For all five of the specimens, either AP or lateral images could not be used to confirm penetration. For two of these specimens, penetration was undetectable in both AP and lateral fluoroscopic images, but a decrease in resistance was recorded.

Conclusion

The described method exhibits greater sensitivity and accuracy for metal penetration to joint, and it is effective in detecting screws in the joints. The novel method described in this paper was applied in a prototype setting, and we believe that this concept can continue to be developed.

Dimensions of the Lateral Malleolar Fossa and Its Potential Violation With Lateral Distal Fibular Plate Fixation

A previously undescribed pitfall of lateral distal fibular locking plates is the risk of violating the lateral malleolar fossa (MF). No previous study has described the dimensions of this fossa. All cases using a lateral distal fibular plate for a fibula fracture from December 2012 to December 2015 (n=365) at a single institution were reviewed. Screws that violated the medial fibular cortical density corresponding to the MF were identified as "at-risk" screws. Available preoperative computed tomography (CT) scans were reviewed (n=69) to measure MF dimensions. Of 365 patients, 115 (31.5%) patients had distal fibular screws at risk of MF violation. There were no significant differences between MF violation and non-violation groups in terms of age, sex, open fracture, syndesmotic fixation, and Weber classification. The MF dimensions were measured on CT scans. Mean height was 12.96 mm (SD, 2.09 mm; range, 9.0-17.3 mm). Mean width was 7.52 mm (SD, 1.37 mm; range, 4.2-10.4 mm). Mean depth was 8.32 mm (SD, 1.59 mm; range, 5.3-11.8 mm). Mean ratio of MF to total fibular width was 0.46 mm (SD, 0.07 mm; range, 0.3-0.65 mm). Mean MF to total fibular depth was 0.42 mm (SD, 0.07 mm; range, 0.28-0.58 mm). There was a difference in dimensions of patients with screws at risk of MF violation compared with those without (MF height: 13.77 vs 12.56, P=.02; MF width: 7.98 vs 7.30, P=.05; MF to fibula width ratio: 0.49 vs 0.44, P=.01; MF to fibula depth ratio: 0.43 vs 0.42, P=.05). The MF violation is a previously unreported but potentially prevalent pitfall of lateral distal fibular plate fixation. Surgeons should be aware of the MF size and exhibit caution when placing screws in the distal locking holes during fibula fixation. [Orthopedics. 2020;43(3):e141-e146.].

Medial malleolus: Operative Or Non-operative (MOON) trial protocol - a prospective randomised controlled trial of operative versus non-operative management of associated medial malleolus fractures in unstable fractures of the ankle

BACKGROUND

There are limited data reporting the outcome of patients with non-operatively managed medial malleolus fractures compared to those treated surgically in the presence of fibular stabilisation for unstable fractures of the ankle. Conservative management could result in fewer complications, reduced surgical time and lower cost. The purpose of this study is to determine if any difference exists in patient reported and surgical outcomes 1 year after surgery between operative and non-operative treatment of medial malleolar fractures in combination with stabilisation of the lateral malleolus.

METHODS/DESIGN

This is a single-centre, prospective, randomised controlled trial that aims to randomise 154 participants with an unstable ankle fracture to 'non-fixation' (n = 77) or 'fixation' (n = 77) of an associated well-reduced medial malleolus fracture following fibular stabilisation. The study will include patients ≥ 16 years of age with a closed bimalleolar or trimalleolar ankle fracture who are able to consent, complete questionnaires in the English language, and complete follow-up over a 1-year period. Randomisation will occur intra-operatively when the medial malleolus fracture is deemed 'well-reduced', with 2 mm or less of fluoroscopic displacement. The technique for fixation of both the medial and lateral malleoli is at the discretion of the operating surgeon. Patient-reported, observer-rated, and radiographic assessments will be collected at baseline and then at the following post-operative assessment points: 2 weeks, 6 weeks and 1 year. Postal questionnaire outcome data will be collected at 3 and 6 months. The primary outcome measure will be the Olerud Molander Ankle Score (OMAS) at 1 year following surgery. Secondary outcome measures will include the Manchester-Oxford Foot Questionnaire (MOXFQ), EuroQol-5D (EQ-5D), pain, treatment satisfaction, time to return to activity, operative tourniquet time, and complications.

DISCUSSION

There is only one previous randomised trial comparing non-fixation with fixation of associated medial malleolus fractures but that was limited by the lack of baseline patient-reported outcome data and an inferior sample size. This current prospective trial aims to provide high-quality evidence regarding the requirement for medial malleolar fixation in unstable ankle fractures.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03362229 . Registered retrospectively on 5 December 2017.